Journal of Environmental Treatment Techniques 2019, Volume 7, Issue 1, Pages: 166-170 166 Comparison of Regression Model and Modified Monod Kinetic Model to Predict the Removal of Ethanol in Trickling Biofilter Amin Goli 1 , Susan Khosroyar 1 , Behroz Vaziri 1 , Fatemeh Sadat Dehghani 2 , Reza Sanaye 3 , Mohammad Mohammadi 2 * 1- Department of Engineering, Quchan Branch, Islamic Azad University, Quchan, Iran 2- Department of Medical Nanotechnology, Shiraz University of Medical Sciences, Shiraz, Iran 3- Department of Cancer proteomics, Shiraz University of Medical Sciences, Shiraz, Iran Received: 10/12/2018 Accepted: 17/02/2019 Published: 30/03/2019 Abstract Ethanol is a toxic compound and a member of volatile organic compounds (VOCs). Ethanol is emitted to the atmosphere by several industries worldwide. Biotrickling filter technology is a well-known technology for removal of VOCs from air. The aim of this study is to compare two regression and modified monod models to predict the removal of ethanol using a biotrickling filter reactor (BTFR). The data of the previous study on ethanol vapor removal by bio-trickling filter were used for determination of r max and K m . Also by these data, a simple regression model was developed. Eventually, ethanol removal efficiency was predicted by both regression and kinetic models. All results were compared with actual data. Our results show that regression model could only predict the average of ethanol removal efficiency. However, kinetic model could additionally predict all changes in ethanol removal efficiency: it has had some good alignment with actual data. Keyword: Ethanol, Kinetic coefficient, Modeling, Biotrickling filter, Biodegradation 1 Introduction 1 The rapid evolution of industries during the last few centuries has left a significant impact on the environment (1-3). The momentous scale of today’s environmental challenges has urged countless number of researchers continuously working in order to provide the best solution for various types of man-made harms dealt to the environment (4-7). Among these is the issue of air pollution caused by the exhaust gasses including ethanol emitted from various industries such as petrochemical and alcoholic drinks manufacturers, often beyond the acceptable capacities (8-10). Ethanol is one of such pollutants and it is categorized into the volatile organic compounds (VOCs), posing threats to the environment (11). Ethanol is widely used in the production of petrochemical compounds. Thus it is only natural to address this issue by considering the threats of this pollutant and its wide-scale usage and generation. In order to achieve reductions in air pollution to attain air quality standards, a set of specific techniques and measures should be identified and implemented. In this particular case, various systems of physical, chemical and biochemical nature have already been utilized so as to treat this pollutant (12-16). However, some of procedures including the physical methods applied by utilizing various adsorbents (17) and the chemical methods (18)  Corresponding author: Mohammad Mohammadi, Department of Medical Nanotechnology, Shiraz University of Medical Sciences, Shiraz, Iran. applied by utilizing chemical scrubbers, are often expensive–these possess even less efficiency in ethanol reduction (19). In contrast, biochemical methods, despite their complications, could prove to be highly appropriate substitutes for the physical and chemical methods (20). The biological methods mostly involve bio-filters. It is to be noted that amongst all these, the trickling biofilters are deemed the most optimum for the elimination of ethanol. The models proposed by researchers to determine the best conditions of applying trickling biofilters, are actually divided into two groups of Micro kinetic and Macro kinetic (21, 22). In Micro kinetic models, it is attempted to take into consideration all parameters involved (23). These may well include the specific surface of the substrate, the thinness of the applied biofilm, the dispersion coefficient of input polluted air into the biofilter, and the constant coefficient of Henry in Mass Transference. These models are usually very complex; they require a vast array of parameters and coefficients which are normally unavailable to the engineers (24). Ottengraf and Van den Over offered one of the most referred-to microkinetic models. The macrokinetic models often avoid defining or investigating partial parameters and would only focus on the most prominent parameters including the concentration of the pollutant, input pollutant debit, and the degree of moisture and temperature. Studying the effects of these parameters on the system efficiency and providing the mathematical relations in the form of macro kinetic models require laboratory experiments; thence they are referred to as the "Experimental models". Generally, in macro kinetic Journal web link: http://www.jett.dormaj.com J. Environ. Treat. Tech. ISSN: 2309-1185